The release of Microsoft's Windows 7 should increase adoption of desktop virtualisation, but won't  cause a massive shift from physical to virtual desktops, according to a VMware executive.

VMware's Bogomil Balkansky, vice president of product marketing, said that Win 7 would bring the topic of desktop virtualisation to the minds of IT pros, and customers he has spoken with seem to be more interested in Win 7 than Vista, he added.

Industry analysts say many IT customers are interested in desktop virtualisation but have been waiting for the introduction of Win 7 to make a wholesale shift to the technology. Migrating from physical to virtual desktops is a potentially enormous project, and many businesses decided it would be inefficient to take the virtualisation leap and then be faced with a separate project to upgrade operating systems

A decision to upgrade employee desktops to Win 7 may also make a CIO think more broadly about a desktop strategy, Balkansky said. "[Windows 7] is very topical and puts the question on the table," he said. "I think it really forces the subject of virtual desktops to become an agenda item in many companies."

But Balkansky does not expect an immediate massive uptick in adoption.

"As you expect, a whole migration to Windows 7 or migration to virtual desktops is something that will not happen overnight," he said.

The switch from XP or Vista to Win 7 could be simplified by virtual desktop technology, however, Balkansky said. For example, desktop virtualisation can minimise the risks of migration by preserving a customer's XP environment. If anything goes wrong with Win 7, the customer can simply revert back to a working state of XP, he said.

"Obviously, Windows 7 poses a challenge for customers, in the sense that migrating hundreds or thousands, or tens of thousands from one generation of a desktop operating system to another is a fairly serious and involved logistical challenge and logistical problem," he said.

In addition to the Win 7 desktop operating system, Microsoft is releasing its new server operating system, namely Windows Server 2008 R2. The server operating system's virtualisation technology will let Microsoft compete more directly against VMware because of features such as live migration, the ability to move running virtual machines from one physical server to another without taking an application down.

Massive adoption of Microsoft's Hyper-V virtualisation software, which is significantly less expensive than VMware's, could deal a huge blow to VMware's core business. Balkansky, while admitting that he is a biased observer, said there are few compelling reasons for customers to switch to Microsoft server virtualisation. VMware delivers a lower TCO per application and "has historically supported more versions of the Windows server operating system than Microsoft itself," he argued.